Distribution of motor heat sources

Abstract

The disclosure is directed to an electrical motor that includes a rotor and stator with improved cooling of the motor. The improved cooling is due to a convenient coil connecting structure of the stator. Outer and inner peripheral connectors connect the coil wound ends at the outer and inner peripheral sides of the stator, respectively. From this structure, heat sources, such as the connectors, are distributed to both the outer peripheral and inner peripheral sides of the stator core. In this manner, the motor may more effectively be cooled through the distributed heat sources.

1. A motor comprising:
 a rotor comprising a plurality of permanent magnet; 
 a stator opposed to the rotor and having a plurality of stator cores formed in an annulus; 
 a plurality of coils with each of the coils being wound around a respective one of the stator cores, each of the coils having an outer peripheral coil wound end disposed on an outer peripheral side of the stator cores and an inner peripheral wound end on an inner peripheral side of the stator cores; 
 a plurality of outer peripheral connectors connecting the outer peripheral coil wound ends via the outer peripheral side of the stator cores; and 
 a plurality of inner peripheral connectors that connect the inner peripheral coil wound ends via the inner peripheral side of the stator cores, 
 at least three of the coils being serially connected by alternating outer and inner peripheral connectors. 
 
   
   
     2. The motor of  claim 1 , wherein
 one of the outer peripheral connectors and one of the inner peripheral connectors are associated with one of a plurality of phases of the coils. 
 
   
   
     3. The motor of  claim 1 , wherein
 the inner peripheral coil wound ends are disposed at a protruding end of one of the stator cores, and wherein the outer peripheral coil wound ends are disposed at a base of one of the stator cores. 
 
   
   
     4. The motor of  claim 3 , wherein
 the coils are wound from the inner peripheral side of one of the stator cores. 
 
   
   
     5. The motor of  claim 1 , wherein
 the coils comprise an odd number of stages. 
 
   
   
     6. A motor comprising:
 a rotor comprising a plurality of permanent magnets; 
 a stator comprising a plurality of stator cores adjacent to a periphery of the stator; 
 means for conducting an electrical current around the stator cores, the means for conducting an electrical current comprising a plurality of coils with outer peripheral coil wound ends disposed on an outer peripheral side of the stator cores and inner peripheral coil wound ends disposed on an inner peripheral side of the stator cores; 
 outer means for connecting the outer peripheral coil wound ends at the outer peripheral side of the stator cores; and 
 inner means for connecting the inner peripheral coil wound ends at the inner peripheral side of the stator cores, 
 at least three of the coils being serially connected by alternating the outer and the inner means for connecting. 
 
   
   
     7. The motor of  claim 6 , wherein
 the means for connecting the outer peripheral coil wound ends and the means for connecting the inner peripheral coil wound ends are associated with one of a plurality of phases of the means for conducting an electrical current. 
 
   
   
     8. The motor of  claim 6 , wherein
 the means for conducting an electrical current is wound from the inner peripheral side of one of the stator cores. 
 
   
   
     9. The motor of  claim 6 , wherein
 the inner peripheral coil wound ends are disposed at a protruding end of one of the stator cores, and wherein the outer peripheral coil wound ends are disposed at a base of one of the stator cores. 
 
   
   
     10. The motor of  claim 6 , wherein
 the means for conducting an electrical current comprises an odd number of stages. 
 
   
   
     11. A motor comprising:
 a motor case that allows a rotor axis to rotate within the motor case; a rotor attached to the rotor axis, wherein 
 the rotor comprises a plurality of permanent magnets disposed along a periphery of the rotor; 
 a stator opposed to the rotor within the motor case; 
 a plurality of coils disposed along a periphery of the stator; 
 a plurality of stator cores formed in an annulus, wherein 
 the coils comprise outer peripheral coil wound ends disposed on an outer peripheral side of the stator cores and inner peripheral coil wound ends on an inner peripheral side of the stator cores; 
 a plurality of outer peripheral connectors that connect the outer peripheral coil wound ends via the outer peripheral side of the stator cores; and 
 a plurality of inner peripheral connectors that connect the inner peripheral coil wound ends via the inner peripheral side of the stator cores, 
 at least three of the coils being serially connected by alternating outer peripheral connectors and inner peripheral connectors. 
 
   
   
     12. The motor of  claim 11 , wherein
 the coils conduct an electrical current in three phases, wherein 
 each phase is associated with one of the outer peripheral connectors and one of the inner peripheral connectors. 
 
   
   
     13. The motor of  claim 11 , wherein
 the inner peripheral coil wound ends are disposed at a protruding end of one of the stator cores, and wherein the outer peripheral coil wound ends are disposed at a base of one of the stator cores.